Parmesan hacks

If you have fresh parmesan in the fridge, you invariably end up with a piece of hardened crust that seems unusable. But through the magic of the microwave, Food Geekery suggests there is a window of opportunity for bringing back your parmesan crusts.
The key is to let it puff up in the microwave, sort of like popcorn, until the popping stops somewhere between 30 and 90 seconds. If you’ve done it wrong, it will either be too hard or burnt. After a brief rest period, the parmesan is ready to eat or be used in a dish.